ATTACHMENT FOR A GRAB IMPLEMENT

Abstract: A grab implement comprising a fixed part (31) and a movable part (30) pivotally coupled thereto to form a grab, the fixed part (31) having a continuous rear wall member (2) and a continuous floor member (4) projecting forwardly therefrom, the floor member (4) having a cutting edge along the leading edge thereof.

Description: ATTACHMENT FOR A GRAB IMPLEMENT Field of the Invention The present invention relates to a grab implement for use in cutting blocks of solid material, and more particularly to a grab implement for attachment to a powered vehicle, for example an agricultural vehicle such as a tractor. Background to the Invention In agricultural equipment, a known type of silage grab is attached to the powered front or rear loader of a tractor, the attachment comprising a base constituted by a plurality of spaced apart tines with a movable jaw operable about a horizontal pivot axis and including a further set of tines which are closed at right angles to the base tines after the base tines have been driven into a silage clamp, to tear out a load of silage. An example of such a silage grab is described in British Patent 1536937, the entire disclosure of which is incorporated herein by reference. Silage grabs using tines are apt to leave a ragged surface on the sides and face of the silage clamp after a load has been removed, and this surface can support secondary fermentation and hence spoilage of the clamp. UK Patent Application No. 2191992, the entire disclosure of which is incorporated herein by reference, discloses a silage grab which comprises a fixed part having a back wall and a plurality of tines projecting forwardly from the lower part of the back wall with said tines being drivable into a silage clamp, a moving part of the grab being pivotally connected to the fixed part about a generally horizontally extending rotational axis and having a front wall with a cutting edge along the lower part thereof, a drive means being connected between the fixed part and moving part and arranged to forcibly drive the cutting edge of the moving part downwardly about said axis to be adjacent the ends of the tines, the parts constituting the front wall lying along an arc about the rotation axis, the arc being that described by the cutting edge during movement. The downward action of the cutting edge in the grab of GB 2191992 give a smoother vertical side to the cut silage, but can cause tearing of the bottom of the grabbed silage load if insufficient tines are present. In addition, the grab suffers from the drawback that because the floor of the grab is formed from spaced-apart tines, the grab cannot be used to transport granular or particulate material, such as barley or feed concentrate. This has the associated disadvantage that the user of the silage grab must carry out the time consuming task of changing the grab implement for a shovel when the implement is to be used for transporting other feed materials. Summary of the Invention The present invention provides a grab implement having a continuous floor member provided with a cutting edge which is suitable for transporting silage and other animal feed materials. In a first aspect the present invention provides a grab implement comprising a fixed part and a movable part pivotally coupled thereto to form a grab, the fixed part having a continuous rear wall member and a continuous floor member projecting forwardly, the floor member having a cutting edge along the leading edge thereof. It can be seen that the present invention obviates the need for tines providing a cutting edge along the leading edge of the fixed part of the grab, and by providing the fixed part with a continuous floor member enables the grab implement to be used as a scoop or shovel for conveying granular or particulate loads. By "continuous" in this specification is meant that the member is substantially able to hold back and prevent the passage of granular or particulate agricultural loads, therethrough, but the possibility is not excluded that the member may have a number of holes or slots whose size is insufficient to allow a substantial quantity of the load to escape. In another aspect, the invention provides a fixed part for a grab implement, the grab implement comprising a fixed part and a movable part pivotally coupled thereto to form a grab, the fixed part comprising a continuous rear wall member and a continuous floor member projecting forwardly therefrom, the floor member having a cutting edge along the leading edge thereof. Preferably the fixed part comprises a generally bucket- shaped member comprising a plurality of gusset members extruding between the rear wall member and the floor member. Preferably gusset members form continuous side members for the fixed part. Where the grab implement is of relatively narrow width, for example less than about 0.6 metres, the side members may be the only gusset members present. Where the width of the grab implement is greater than about 0.8 metres in width, further strengthening gusset members are preferably provided, spaced across the width, preferably at intervals of from about 0.4 to 0.6 metres apart. Preferably at least the side members and preferably any other gusset members present are provided with cutting edges to assist the cutting action of the cutting edge on the floor member. Preferably the cutting edge of the floor member is substantially straight and extends across the entire width of the floor member. In other embodiments the cutting edge may be V-shaped, or V-shaped sections arranged side-by-side. The cutting edge or edges are preferably formed from high tensile material, for example, high tensile steel. In order to protect the cutting edge on the floor member from damage by ground contact it is preferably slightly raised, and this can conveniently be done by providing a supporting means beneath the floor member to raise the floor member slightly off the ground. The supporting means can comprise, for example, a supporting wear strip arranged around the sides of the underside of the floor member. The supporting wear strip may have a height of, for example, from 10 mms to 40 mms. As a further protection for the cutting edge the floor member, edge protectors are preferably provided which extend forwardly of the cutting edge. These edge protectors may be pointed or bullet-shaped and extend up to 25 mms or more in front of the cutting edge. The edge protectors can help to prevent damage to the cutting edge due, for example, to contact with vertical walls against which silage or granular material or other animal feed may be stacked. Two or more such edge protectors may be provided, for example, at each end of the cutting edge, and, if necessary, at points intermediate the ends. In a preferred embodiment, the fixed part further comprises ejector means for ejecting solid material carried by the grab attachment therefrom. The ejector means may comprise at least one elongate member attached at one end thereof to the rear member and the other end of which protrudes through a narrow elongate slot in the floor member, wherein the end of the or each elongate member protruding through said respective slot is adapted to move relative to the rear member. The or each elongate member is preferably pivotally attached to the rear member. Two or more such elongate members may be provided, which can be joined by a horizontal bar to form an ejector gate operated by ground contact. Alternatively, the ejector means may be a hydraulically operated ejector gate. The fixed part is pivotally coupled to a movable part to form a grab implement. Preferably the movable part is pivotally connected to the fixed part about a generally horizontally extending rotational axis. The movable part of the grab implement preferably comprises a front wall member with a cutting edge along the lower front edge thereof. A suitable grab implement movable part is described in GB 2191992. Preferably the movable part is provided with continuous side members, which are preferably provided with cutting edges on their lower edges. Preferably the grab implement is provided with drive means, which can, for example, be hydraulically operated, and which is arranged to drive the cutting edge of the movable part in an arc towards the cutting edge on the floor member. In order that the invention can be better understood, preferred embodiments thereof will now be described, by way of example only, with reference to the accompanying Drawings, in which:- Figure 1 shows a perspective view of a first embodiment of a bucket base for a grab implement according to the invention; Figure 2 shows a perspective view of a second embodiment of a bucket base for a grab implement according to the invention showing a ground-operated ejector gate; Figure 3 shows a perspective view of an assembled grab implement according to the invention; Figure 4 shows a perspective view of a third embodiment of a bucket base for a grab implement according to the invention; Figure 5 shows a perspective view of a fourth embodiment of a bucket base for a grab implement according to the invention; and Figure 6 shows a perspective view of a fifth embodiment of a bucket base for a grab implement according to the invention. Referring in detail to Figure 1, which is not drawn to scale, there is shown a fixed part 1 for attachment to an agricultural implement (not shown) such as a tractor front loader or farm shovel. The fixed part 1 can be attached to either the front or the rear of a tractor. The fixed part 1 comprises a continuous rear plate 2 having a pivot attachment 3 for accommodating a movable part, which will be described below and which has been omitted from Figure 1 for reasons of clarity. A floor plate 4 of mild steel or a high tensile material such as high tensile steel is attached by any suitable means, such as welding, to the rear plate 2 and generally at right angles thereto, and a plurality of generally right- angled gusset plates 5 (four are shown in Figure 1) are attached to the rear plate 2 and floor plate 4 such that two of the gusset plates 5a, 5b form the side walls of the fixed part 1. The two gusset plates 5 between the sides of the attachment (the intermediate gusset plates) are slightly shorter in base length than those forming the sides of the fixed part 1 so that there is a space between the intermediate gusset plates 5 and the front edge 6 of the floor plate 4 of the order of 25mm. The intermediate gusset plates 5 are also slightly shorter in height than those forming the sides of the fixed part 1 so that the upper edges of the intermediate gusset plates 5 meet the rear plate 2 at points lower than those at which the upper edges of the side plates 5a, 5b meet the rear plate 2. Knife edges 7, generally 10mm in thickness and formed from high tensile steel are either attached to or formed in the sloping edge of each gusset plate 5 and the front edge 6 of the floor plate 4 is also provided with a knife edge 8. The knife edge 8 attached to the front edge 6 of the floor plate 4 can be either straight, a single V- shaped member, a plurality of V-shaped members, or any other suitable shape, as will be described hereinafter. The knife edge 7 is protected by edge protectors 9, 10 each of which is in the form of bullet- or spear-shaped projections of high tensile steel positioned so as to protrude from the front of each knife edge 7 and the sides of the fixed part 1. Figure 2, in which parts common to the embodiment of Figure 1 are designated by like reference numerals, shows a fixed part 20 similar to that of Figure 1 but having three elongate slots 13 extending through the floor plate 4 from the rear plate 2 towards the front edge 6 of the floor plate 4. It will be appreciated that the number of slots 13 will depend upon the width of the fixed part 1. For example, one, two or more than three slots 13 could be used. An ejector gate comprises three elongate leg members 14, each of which has an upper end 15 hinged to the rear plate 2 and a lower end 16 which protrudes through the respective slot 13, when the leg member 14 is in its lowered position, so that the lower ends 16 can engage the ground when the attachment 1 rests on the ground. The leg members 14 are joined together to form a gate by means of a transversely extending rigid bar 17. Figure 3 shows a grab implement 30 incorporating the features of the embodiments of Figures 1 and 2, and parts common to those embodiments are designated by like reference numerals. The grab implement 30 further includes a movable part 18 pivotally attached to the pivot attachment 3 provided at both sides of the rear plate 2 and is movable relative to the floor plate 4 by means of two hydraulic rams 19, each of which connects the upper edge 21 of the movable part 18 to the upper edge 22 of the rear plate 2. The cover member 18 also comprises two side walls 23 and a curved front wall 24, each of which is provided at its lower edge with a knife edge 25. As is the case with the knife edges provided on the fixed part 1, the knife edges 25 provided on the cover member 18, may be serrated. Referring now to Figure 4, there is shown a fixed part 40 for a grab implement, which is of welded construction and is provided with side members 41 and three gussets 42. The leading edge 43 of the floor plate 44 is V-shaped and provided with a knife edge 45. The side members and gussets also have knife members 46 on their upper edges. Figure 5 shows a fixed part 50 for a grab implement similar to that of Figure 4, except that the leading edge 51 of the floor plate 52 is serrated and provided with a serrated knife member 53. Finally, Figure 6 shows a fixed part 60 for a grab implement which is provided with a raised cutting edge and cutting edge protectors. The fixed part 60 comprises a continuous rear wall plate 61 and an 8mm thick mild steel floor plate 62 welded at right angles thereto. Side members 63, 64 and gussets 65, 66 are welded to the rear plate and the floor plate respectively. The gussets 65, 66 have a leading angle of generally 30° and extend to within 25mm of the leading edge 67 of the floor plate 62. Welded to the leading edge 67 is a 60mm wide x 10mm thick high tensile steel knife edge 68 with a front sloping edge forming a knife blade of 25mm. The side members and gussets are also provided with cutting knife edges on their upper edges. The side edges and rear edge of the underside of the floor plate 62 are framed by 60mm wide x 15mm thick wear bars 69, 70, 71 respectively of high tensile steel which are screwed or welded thereto. The side wear bars 69, 71 are extended forwardly of the knife edge 68 and have tapered extensions 72, 73 acting as edge protectors. The operation of the embodiments of the invention will now be described with particular reference to Figure 3, although it will be appreciated that the embodiments of Figures 1, 2, 4, 5 and 6 operate in a similar manner. When a load of silage is to be cut from a silage clamp, a tractor or other suitable vehicle (not shown) carrying the grab implement 30 is driven towards the silage until the knife edge 8 provided on the floor plate 4 and the knife edges 7 on the side members 5a, 5b and gusset plates 5 penetrate into the silage. This step of the operation is carried out with the movable part 18 in its raised position. In this case, when the fixed part 31 has penetrated into the silage to a sufficient extent, the movable part 18 is lowered by the hydraulic rams 19 and the knife edges 25 arranged on the lower edges of the cover member 18 sever a block of silage of the desired size from the larger block. The vehicle carrying the attachment 1 is then reversed and driven away from the clamp while carrying the load of silage inside. When it is desired to eject the load of silage from the grab implement 30, the grab implement 30 is lowered until the lower ends 16 of the leg members 14 of the ejector gate engage the ground. If the vehicle is then reversed, the lower ends 16 of the leg members 14 move towards the front edge 6 of the floor plate 4 , thus pushing the load of silage towards the front edge 6. The lower ends 16 remain in contact with the ground sufficiently long for part of the load of silage to protrude beyond the front edge 6 of the floor plate 4 and itself engage the ground. As the vehicle is then reversed further, the load of silage remains in contact with the ground and is completely removed from the grab implement 30. It will be appreciated that the silage or other material carried by the grab implement 30 can also be tipped out of the fixed part 1, as well as being removed by the ejector gate. Whilst the invention has been described in relation to the cutting of silage in agriculture it will be appreciated that many other uses are possible. The reader's attention is directed to all papers and documents which are filed concurrently with this specification and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference. All the features disclosed in this specification (including any accompanying claims, abstract and drawings) , and/or all of the steps or any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive. Each feature disclosed in this specification (including any accompanying claims, abstract and drawings) , may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

Claims: CLAIMS 1. A grab implement comprising a fixed part and a movable part pivotally coupled thereto to form a grab, the fixed part having a continuous rear wall member and a continuous floor member projecting forwardly therefrom, the floor member having a cutting edge along the leading edge thereof. 2. A grab implement according to Claim 1, in which the fixed part comprises a generally bucket shaped member. 3. A grab implement according to Claim 1 or 2, in which the fixed part comprises a plurality of gusset members extending between the rear wall member and the floor member. 4. A grab implement according to Claim 3, in which gusset members form continuous side members for the fixed part. 5. A grab implement according to Claim 3 or 4, in which strengthening gusset members are spaced across the width of the fixed part at intervals of from substantially 0.4 metres to substantially 0.6 metres apart. 6. A grab implement according to any of Claims 3 to 5, in which the side members and any other gusset members are provided with cutting edges on their upper edges. 7. A grab implement according to any of the preceding Claims, in which the cutting edge on the floor member is substantially straight. 8. A grab implement according to any of Claims 1 to 6, in which the cutting edge on the floor member is V- shaped. 9. A grab implement according to any of Claims 1 to 6, in which the cutting edge on the floor member is serrated. 10. A grab implement according to any of the preceding Claims, in which supporting means is provided beneath the floor member to raise the cutting edge slightly above the ground. 11. A grab implement according to Claim 10, in which the supporting means comprises a wear strip arranged around the side edges and rear edge of the underside of the floor member. 12. A grab implement according to Claim 10 or 11, in which the supporting means has a height of from substantially 10 mms to substantially 40 mms. 13. A grab implement according to any of the preceding Claims, in which the cutting edge along the leading edge of the floor member is provided with edge protectors which extend forwardly of the cutting edge. 14. A grab implement according to Claim 13 in which the edge protectors are provided at each end of the cutting edge. 15. A grab implement according to any of the preceding Claims, in which the fixed part is provided with ejector means for ejecting solid material from the grab attachment. 16. A grab attachment according to Claim 15, in which the ejector means comprises an ejector gate operated by ground contact. 17. A grab attachment according to Claim 15, in which the ejector means comprises a hydraulically operated ejector gate. 18. A grab implement according to any of the preceding Claims, in which the movable part is pivotally connected to the fixed part about a generally horizontally extending rotational axis. 19. A grab implement according to any of the preceding Claims, in which the movable part comprises a front wall member with a cutting edge along the lower front edge thereof. 20. A grab implement according to Claim 19, which is provided with drive means arranged to drive the cutting edge of the movable part in an arc towards the cutting edge on the floor member of the fixed part. 21. A grab implement according to any of the preceding Claims, substantially as hereinbefore described with reference to and as illustrated in the accompanying Drawings. 22. A grab implement substantially as hereinbefore described. 23. A fixed part for a grab implement, the grab implement comprising a fixed part and a movable part pivotally coupled thereto to from a grab, the fixed part comprising a continuous rear wall member and a continuous floor member projecting forwardly therefrom, the floor member having a cutting edge along the leading edge thereof. 24. A fixed part according to Claim 23, having any of the features of Claims 2 to 16. 25. A fixed part according to Claim 23 or 24 substantially as hereinbefore described with reference to and as illustrated in the accompanying Drawings. 26. A fixed part for a grab implement substantially as hereinbefore described.

Inventors: TAYLOR WILLIAM, TAYLOR, WILLIAM
Applicants: TAYLOR WILLIAM, TAYLOR, WILLIAM
Application year: 1994
Main classification: A01F25
IPC codes: A01F25, E02F3